Update some uses of char16 to use the base:: namespace.

ui/views/controls/textfield/textfield_views_model.h

Index: ui/views/controls/textfield/textfield_views_model.h
diff --git a/ui/views/controls/textfield/textfield_views_model.h b/ui/views/controls/textfield/textfield_views_model.h
index 4e625c4d2d65b2f823d047f15f0a3c4e2e355584..bc1de8857529a59ccd7b62b62e15259fc311bb68 100644
--- a/ui/views/controls/textfield/textfield_views_model.h
+++ b/ui/views/controls/textfield/textfield_views_model.h
@@ -82,7 +82,7 @@ class VIEWS_EXPORT TextfieldViewsModel {
   }
 
   // Inserts a character at the current cursor position.
-  void InsertChar(char16 c) {
+  void InsertChar(base::char16 c) {
     InsertTextInternal(base::string16(&c, 1), true);
   }
 
@@ -93,7 +93,7 @@ class VIEWS_EXPORT TextfieldViewsModel {
   }
 
   // Replaces the char at the current position with given character.
-  void ReplaceChar(char16 c) {
+  void ReplaceChar(base::char16 c) {
     ReplaceTextInternal(base::string16(&c, 1), true);
   }